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FIELD MUSEUM OF NATURAL HISTORY
ZOOLOGICAL SERIES VOL. XII, No. 7
NEW SALAMANDERS OF THE GENUS OEDIPUS
WITH A SYNOPTICAL KEY
E. R. DUNN
Department of Zoology, Smith College
REPORTS ON RESULTS OF
THE CAPTAIN MARSHALL FIELD EXPEDITIONS
WILFRED H. OSGOOD
Curator, Department of Zoo] f&L \yflflNKi OF THE
CHICAGO, U. S. A.
May 19, 1924
NEW SALAMANDERS OF THE GENUS OEDIPUS
BY E. R. DUNN.
Through the courtesy of the Field Museum of Natural History in
loaning their collections of salamanders of the genus Oedipus for study
in connection with the revision of the Plethodontidae, on which I have
been engaged for some time, I am enabled to add to the number of
described species, and to clear up the status of some forms hitherto
A good many new forms of Oedipus have been described since the
last general discussion of the genus. The various expeditions of the
Field Museum of Natural History, of the Museum of the University
of Michigan, and of the Museum of Comparative Zoology, during the
year 1923, have brought to light three more new species and good series
of two forms hitherto very poorly represented in collections. One of
these, Oedipus parvipes Peters, breaks down the distinction between the
normal forms of the genus and the wormlike forms frequently referred
to Oedipina. Therefore, it seems appropriate to append to the descrip-
tions of these three new forms a brief synopsis of the whole genus.
This is based on somewhat uneven material, the mountain forms being
usually well known, while the lowland species are still represented in
collections by very few specimens. Of the 30 species recognized here-
inafter, I have seen specimens of 29, the missing one being the perhaps
mythical salamander from Haiti. These 29 forms are represented by
a series of 564 specimens preserved in various museums in America.
The genus Oedipus is closely allied to and perhaps derived from
the wide-ranging northern genus Hydromantes. These two represent
the terrestrial wing of the f ree-tongued Plethodontidae, as Gyrinophilus,
Pseudotriton, and Eurycea represent the mountain-brook wing. I
conceive these two to be parallel series, Hydromantes and Gyrinophilus
(with their primitive double premaxillae) standing at their bases.
Hydromantes differs from Oedipus in having double premaxillae, and
in lacking the basal constriction of the tail. The "Oedipina" forms of
Oedipus lack this constriction, but are degenerate in other ways as
well, and are completely connected with normal Oedipus by parvipes.
The genus is large and varied, but the very different extremes are
connected by intermediate forms.
96 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. XII.
Oedipus schmidti sp. nov.
Type from mountains west of San Pedro, Honduras, at 2000 feet,
on trail. No. 4538 Field Museum of Natural History. Adult female.
Collected May 5, 1922, by K. P. Schmidt.
Range. Known only from type locality.
Diagnosis. A large Oedipus, with groove from eye to gular fold;
feet well developed, almost entirely webbed; vomerine teeth 20, series
extending beyond nares; lead gray, with indistinct black spots.
Description of Type. 13 costal grooves; 3 costal folds between ap-
pressed toes ; head width 4% in length from snout to vent ; head length
3^ in length of body; head a truncated oval as seen from above; eye
longer than its distance from tip of snout; outline of upper jaw con-
cave as seen from side; angle of jaw back of hind angle of eye; both
eyelids fitting under a fold of skin behind ; a groove from eye to gular
fold ; a groove from this down behind angle of jaw ; limbs well devel-
oped; fingers 3, 2, 4, i in order of length, last joint of 3 free, rest
entirely in web; toes 4, 3, 2, 5, i in order of length, last joint of 3
and 4 almost free, rest entirely in web; anal lips smooth; tail longer
than body, terete, a basal constriction; vomerine teeth 20 in series,
beginning beyond outer border of nares, running nearly straight in
and then a little back, separated from its fellow by such a distance as
would result from the lack of one tooth of a series, separated from
parasphenoids, by a little over the diameter of the nares; latter in a
single patch divided posteriorly, beginning opposite anterior fourth of
nares; leaden gray above, lighter below; small irregular black spots on
sides of body and tail ; total length 195, head 24, body 83, tail 88.
Remarks. This species seems quite close to robustus of Costa Rica,
differing mainly in the greater webbing of the toes, in the presence of
black spotting on the sides, and in the absence of the white ring around
the base of the tail. It is known only from the type.
Oedipus colonneus sp. nov.
Type from La Loma, on trail from Chiriquicito to Boquete, alti-
tude about 2000 feet, Bocas del Toro, Panama. No. 9406 Museum of
Comparative Zoology. Adult female. Collected by E. R. Dunn and
Range. Known only from type locality.
Diagnosis. An Oedipus with fully webbed toes; no teeth on
maxilla; vomerine teeth 9, beginning behind inner edge of nares; belly
MAY, 1924. NEW SALAMANDERS DUNN. 97
light gray ; dorsal surface reddish gray much obscured by darker streak-
ing; a dermal ridge across head and eyelids.
Description of type, 13 costal grooves; 4 costal grooves between
appressed toes ; head width 6 in length from snout to vent ; head length
3^ in length of body; head truncate, nostrils at angles; eye less than
its distance from tip of snout ; snout swollen ; a tubercle below nostril ;
outline of upper jaw convex as seen from side; angle of jaw back of
hind angle of eye ; upper eyelid fits over lower behind ; a dermal ridge
across head between eyes, extending onto eyelid ; an additional tubercle
on eyelid posterior to this; grooves of head obsolete; limbs well devel-
oped ; fingers and toes palmate ; third finger and third toe longest, their
tips projecting slightly beyond web; tail constricted at base; anal lips
smooth; tail longer than body; vomerine teeth 9 in series, beginning
behind inner edge of nares, extending in and back, separated from its
fellow by width of nares and from parasphenoids by twice that dis-
tance; parasphenoids in a single patch beginning opposite middle of
eye socket ; no teeth on maxilla ; reddish gray above ; light gray below ;
on dorsal surface and sides the ground color is obscured by brownish
black streaking, and shows clearly only on top of the head; total
length 82, head 10, body 32, tail 40.
Habits. This specimen was caught at night as it sat on a leaf
about a foot from the ground near a small brook. It was sluggish.
Remarks. The dermal ridge across the head is unique in the genus.
Unfortunately only a single specimen was secured so that possibly it
is abnormal, although it has every appearance of normality. The
relationships are not very evident. The other palmate species without
maxillary teeth is rufescens, and it may be allied to that form or to
striatulus, another small species with dorsal streaking. The specimen,
although a female, shows a strongly swollen snout.
Oedipus nasalis sp. nov.
Type from mountains west of San Pedro, Honduras, at 4500 feet
altitude. No. 4568 Field Museum of Natural History. Adult male.
Collected April i, 1923, by K. P. Schmidt and Leon L. Walters.
Range. Known only from type locality.
Diagnosis. A small Oedipus with nostrils large in adult; toes
webbed at base; 2-3 costal folds between appressed toes.
Description of type. 13 costal grooves; 2 costal folds between ap-
pressed toes; head a blunt oval; head width 4^ in length from snout
98 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. XII.
to vent ; head length about 4 in length of body ; snout swollen, a tubercle
below nostril; nostril larger than pupil; outline of upper jaw sinuous
as seen from side; angle of jaw below hind angle of eye; both eyelids
fitting under a fold of skin behind; a groove from eye to gular fold;
a branch from this down behind angle of jaw; limbs well developed;
fingers 3, 4, 2, I in order of length, last two phalanges of 3 free ; toes
3, 4, 2, 5, i in order of length, last two phalanges of 3 free ; tail longer
than head and body, constricted at base, terete ; anus lined with papillae ;
vomerine teeth 5 in series, beginning behind inner edge of nares, curv-
ing in and back, separated from its fellow by a space equalling the gap
between two teeth of the same series, separated from parasphenoids by
the length of a series ; latter in single patch, beginning opposite middle
of eye-socket; internal nares a slit; premaxillary teeth enlarged, for-
ward, out of line with maxillary teeth; dark grayish brown, lighter on
back, a dark band on sides; a dark triangle, apex backwards, base
between eyes; lighter gray dotted with white below and on sides; two
light spots on base of tail; total length 75, head 6.5, body 25.5, tail 43.
Variation. A female, Field Museum No. 4579, same data, differs
in having the snout not so swollen; no tubercle under nostril; anal
lips smooth; vomerine teeth 8 in series, separated from its fellow by a
gap equalling twice that between two teeth of the same series, sep-
arated from parasphenoids by twice that distance; total length 80,
head 7, body 27, tail 46.
A young specimen, Field Museum No. 4584, same data, has the dor-
sal region covered by a light reddish gray band with scalloped edges, this
band contains irregular darker spots, and two lighter spots above anus ;
a dark band between eyes ; a dark stripe from eye to insertion of arm,
total length 46, head 4, body 17, tail 25; 3 costal folds between ap-
No. 4590, same data, is reddish gray above and on sides, gray below ;
weak and irregular dorsal and lateral dark lines; a dark stripe from
eye to insertion of arm; total length 55, head 5, body 20, tail 30.
Some young have an immaculate dorsal band, and all the young are
marked while most of the adults are almost uniform.
Remarks. This species is closely allied to O. picadoi of Costa
Rica, which has, however, weaker limbs, there being six costal folds
between the appressed toes. The other two forms with large nostrils,
pennatulus and townsendi, have the toes completely webbed.
MAY, 1924. NEW SALAMANDERS DUNN. 99
A KEY TO THE FORMS OF OEDIPUS.
The species of Oedipus form four series, which may thus be out-
I. bellii, schmidti, robustus (a primitive series with no obvious
II. cephalicus (leprosus auct.), rostratum, morio, subpalmatus,
ads perms, altamazonicus, colonneus, rufescens, striatulus, lignicolor,
yucatanus, salvinii, attitlanensis , platydactylus (variegatus auct.). This
series begins with five mountain animals with incompletely palmate feet
and ends with palmate lowland species whose immediate relationships
are uncertain. However, the last five are pretty clearly allied.
III. sulcatus, chiropterus, rex, nasalis, picadoi, townsendi, pen-
natulus. These are all small, mountain species. Four have enlarged
IV. lineolus, infuscatus, parvipes, alfaroi, collaris, uniformis.
These are the "Oedipinas" and have no primitive members and no
obvious connection with any other forms. The Haitian form is per-
Of these four series the most primitive of each is set down first and
is a Mexican species. What I have considered as platydactylus may
prove divisible into two or three races. The key does not pretend to
follow throughout the natural order, being arranged solely with regard
to convenience and ease of determination.
1. Oedipus of normal salamander form, not wormlike, never more than 14
costal grooves, feet and limbs never much reduced, nostrils never large
in adult 2
Oedipus of which the above is not true 21
2. Toes not fully webbed 3
Toes fully webbed 13
3. Large species reaching 195 mm., markings not a light dorsal band,
vomerine teeth 18-20 in series 4
Medium and small species, never over 150 mm., markings usually a light
dorsal band, vomerine teeth at most 15 in series 6
4. Toes nearly free, a double row of yellow spots on back, Mexico bellii
Toes about half webbed, no dorsal markings 5
5. Toes more webbed, no light ring at base of tail, Honduras schmidti
Toes less webbed, a light ring at base of tail, Costa Rica robustus
6. Small species not over 90 mm., toes nearly free, 9 or fewer teeth in
vomerine series 7
Medium species, toes usually half webbed, 9 or more teeth in vomerine
7. Vomerine series very oblique, beginning at inner edge of nares, inner
toe rudimentary, tail longer than head and body, eastern Mexico. . .chiropterus
Vomerine series more transverse, beginning outside inner edge of nares,
inner toe not rudimentary 8
ioo FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. XII.
8. Tail shorter than head and body, western Mexico sulcatus
Tail longer than head and body, Guatemala rex
9. Toes nearly free, a groove from eye to gular fold, Mexico cephalicus
Toes half or more webbed, no groove from eye to gular fold 10
10. Two phalanges of third toe free, Guatemala rostratum
Less than two phalanges of third toe free 1 1
11. One phalange of fourth toe free 12
Less than a whole phalange of fourth toe free, Colombia and Vene-
12. Two very different color phases, one with light belly, Guatemala and
No light color phase, Costa Rica and Panama subpalmatus
13. Belly unpigmented 14
Belly pigmented 15
14. A dorsal light area with large dark spots outlined with light, Pacific
Coast, Mexico to Costa Rica salvinii
Dark with two dorso-lateral light lines, Guatemala and Chiapas . . . attitlanensis
15. Belly striped, yellow and blackish brown, Nicaragua and Costa Rica.striatulus
Belly not striped 16
16. Dorsal area of clear yellow, with or without black spotting or streaking,
Mexico to Honduras platydactylus
Dorsal area not of clear yellow 17
17. Large species over 150 mm 18
Small species under ioo mm 19
18. Legs longer, black with dirty yellowish or reddish dorsal area, Costa
Rica and Panama lignicolor
Legs shorter, brown with ochre mottlings, Yucatan and Guatemala, .yucatanus
19. No maxillary teeth 20
Maxillary teeth present, east face of Andes, Colombia to Bolivia
20. A dermal ridge across head, dark with lighter streaking, Panama . . colonneus
No dermal ridge across head, a lighter dorsal area, Mexico and Guate-
21. Toes free or nearly so (nostrils large) 22
Toes much reduced, entirely webbed 23
22. 2-3 costal folds between appressed toes, Honduras nasalis
6 costal folds between appressed toes, Costa Rica picadoi
23. Not wormlike, nostrils large in adult 24
Wormlike, nostrils not large in adult 25
24. Teeth on maxilla, 4-5 costal folds between appressed toes, Mexico .. townsendi
No teeth on maxilla, 6 costal folds between appressed toes, Mexico, .pennatulus
25. Costal grooves 14 26
Costal grooves 17 or more 27
26. Black, Mexico lineolus
Brownish, Haiti infuscatus
27. Costal grooves 17, Colombia to Panama parvipes
Costal grooves 19-21 28
28. Larger, stouter, head longer, tail constricted at base, Nicaragua to
Smaller, slimmer, head shorter, tail not constricted at base 29
29. Brown, no maxillary teeth, Costa Rica alfaroi
Black, maxillary teeth present, Honduras to Panama uniformis
UBHW1 * 'tt
JUL 1 ' 192*
UNIVERSITY OF IIUHOB